Subtract 63/32 from 21/27, Solve 21/27

Subtract 63/32 from 21/27

1^st number: 21/27, 2^nd number: 1 31/32

21/27 - 63/32 is -343/288.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 32 is 864

Next, find the equivalent fraction of both fractional numbers with denominator 864
For the 1st fraction, since 27 × 32 = 864,
21/27 = 21 × 32/27 × 32 = 672/864
Likewise, for the 2nd fraction, since 32 × 27 = 864,
63/32 = 63 × 27/32 × 27 = 1701/864
Subtract the two like fractions:
672/864 - 1701/864 = 672 - 1701/864 = -1029/864
After reducing the fraction, the answer is -343/288

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